The present invention relates to crank operated vehicles such as a wheeled cart used by children, athletes, disabled persons as well as those requiring locomotion in public places, such as railway terminals and airports.
There are several types of non-motorized vehicles; one such type is generally characterized by the fact that propulsion is effected by the physical strength of the operator, whose power is transmitted directly through an arm with the use of a rod system or chain. The torque thus created ensures the propulsion of the vehicle. Such vehicles are generally known as bicycles or trolleys. Recently another type of sporting and toy-vehicles for children has become known, the chassis of which is formed by flat surface and the wheels are fixed to the axle supporting the chassis eccentrically with the eccentricity of each wheel being in opposition to the other. Propulsion of the vehicle is provided by transferring the center of gravity of the operator's body, the operator standing or sitting on the chassis, while the vehicle performs a rocking motion around the longitudinal axis of the chassis. The eccentric fastening of the wheels actually forms lever arms which are loaded alternately with the power given by transferring the weight of the body. The forces developed by the load create a torque, that keeps the vehicle in motion. The disadvantage of this vehicle, is its unsteerability, e.g. running in a predetermined track or direction is impossible. Thus, it did not gain general acceptance either as a toy, a vehicle or as an exercise device.
The present invention has as its object the improvement of such vehicles as hereinbefore described having a chassis and at least one drivable crank system consisting of a pair of driving wheels fixed with opposite eccentricity to the driving shaft supporting the chassis.
It is a further object to provide a vehicle of the type described in which its steerability is improved and can be driven in a straight line or track.